Automatic batch furnace apparatus



Dec. 25, 1956 w. N. 'YOUNG AuToMATw BATCH FURNACE APPARATUS 4 Sheets-Sheet l Filed March 13, 1953 i\\ 'lli A lNvENToR WALTER N. YOUNG B'Y ATTORN EY W. N. YOUNG AUTOMATIC BATCH FURNACE APPARATUS Dec. 25, 1956 Filed March 13, 1953 4 Sheets-Sheet 2 INVENTOR WALTER N. YOUNG ATTORNEY 4 w. N. YOUNG 2,775,440

AUTOMATIC BATCH FURNACE APPARATUS 4 Sheets-Sheet 3 Dec. 25, 1956 Filed March 15, 1955 Dec. 25, 1956 l w, N YOUNG 2,775,440

` AUTOMATIC BATCH FURNACE APPARATUS Filed March 13, 1953 A 4 Sheets-Sheet 4 v E L ATTORNEY :fthe-apparatus.

United States Patent O c 2,175,440 e Y AUTOMATICBATCH FURNACE APPARATUS I Application `March 13, 1953, Serial No. 342,067

Claims. (Cl. 263-7) The invention is concerned with an apparatus for treat ing articles `in a furnace by an automatically controlled batchpwtype of operation. The apparatus is particularly adapted `to the deposition ofcarbon on small ceramic bodies or substrates in the making ofdeposited carbon resistors... 1 j Y The manufacturing processes for such articles involve thefapplication and maintenance of particular conditions of gaseous mixtures under particular temperatures in closed chambers for considerable periods of time which may total several hours and to ensure articleswhich are uniform incharacter and of high quality requires careful and exacting control of various critical factors. Attempts torneet the conditions by an apparatus designed to operate on the continuous principle have encountered various difilculties which the, present larrangement avoids.

, The `apparatus of the present inventionachieves a high i quality product and adequate production capacity andefciency in a machine combination adapted to operate on the batch principle. lts general` features include the combination of a furnace and associated mechanism in which a` plurality of treating flasks are`deta`chably mounted on a movable support which is bodily translatable and 'also ro- 4tat'able whereby the ilasks may be successively positioned in the furnace each ilask in 4addition being individually v andl independently rotatable 'on its ownaxis. While .one

flask is being treated in the furnace, the other ask or flasks may undergo a suitable cooling period which is normally necessary before the articles may beexposed to the atmosphere. "These functions therefore are carried on simultaneouslylwith a corresponding increase in eillciency and capacity of the apparatus.

f The invention accordingly comprises the features of construction,combination of elements, and arrangement of parts, which will be exemplified in the construction hereinafter set forth, and the scope of the invention will be indicated inr the claims. i i

` jg-Fo afuller understanding of `the nature and objects of the invention reference should behad to the following detailed description; taken in connection With the accompanying drawings, in which:

Fig. l is a view in elevation from the side of the com- -pleteasse'mbled apparatus;

Fig. 2 isfa topplanview thereof;

lFig. 3 `is a vertical fragmentary View taken on the line 3L3 of Figure l` showing particularly the carriage traversing means and the ilaskrotating means;

e y Y 2,775,440 c kPatented Dec. 25, 1956 V" v ree the front of a furnace 11. The machine is designed removably to support a pair of containers 12 and 12a comprising specifically flasks of `ceramic material adapted to contain the articles to be coated, the coating process involving the` insertion of the llask into the furnace and the supply to theinterior of the llask while it is subjected to the furnace temperatures of appropriate gases, as will be described in more detail.

The furnace is provided with suitable closure means adapted to be opened to permit the insertion in the furnace of the respective deposition tlask. The particular closure means shown comprisesa pair of doors 13, 13a supported on a common pivot 14 by means of appropriate bracket parts 15 (Figs. l and 4). To admit a llask to the furnace the doors are swung open to the positions shown in dotted lines in Figure 4 by suitable automatically controlled power means comprising in the present case a pneumatic cylinder `16 for each of the doors pivoted to the furnace frame structure at 17.` Operating in each cylinder isa piston connected to the piston rod 18 the outer end of the piston rod being pivoted at 19 Vto a lug extending from the respective furnace door. The particular arrangement of operating means and controls may be varied but .the operation may be suitably effected by the admission of air throughthe pipes 20, the air being supplied through a conduit 2li under the control of valve 22 which is adapted to be operated by electrical solenoid means. In general, admission of air through the pipes 20 causes the piston rods 18 to be moved outwardly opening the doors and shifting of the valve 22 releases the airp'ressure permitting the pistons to be moved' inwardly by compression springs 23 lo cated interiorly of the cylinders. e The flasks 12 and 12a aremountedon a carriage 30 pro vided with two pairs of supporting rollers 31 adapted to travel on the horizontal spaced tracks 32 whereby the carriagemay be translated along the tracks to advance the corresponding flasks vinto the furnace and retract it.

The carriage supporting tracks 32 form part ofa turntable which include frame beams 33 upon which the tracks are supported, joined together by cross frame members 34 and having a depending central cylindrical bracket part 35. The under part ofthe carriage also has depending therefrom four angularly spaced brackets 36 each carrying a roller 37 adapted to ride on a circular track 38 which is rigidly supported on the main frame part 10.

The turntable is adapted to be-oscillated through an angle of 180 to bring selectively either of the flasks 12 f Figi'4 is a view in elevation looking at the front of the furnace showing the door arrangement;

Fig. 5fis a detail crossr'sectionalview of the spindle means forsupporting and'r'otating the llask and includes details of the means for detachably securing the Vflask to -thesupporting spindle; and

. ".Fig. 6 is an electrical circuit diagram of the controls for ,3 Thefparticularapparatus disclosed as an exempliica- `tMnof the, principles of the linvention embodies an operating mechanism supported on a basel!!v locatedadjacent or 12a into position in front of the furnace. As Will be later pointed out, various conduits for admitting gases to the ilasksextend from stationary positions to the spindle mountingfor the flasks and` to avoid progressive accumulative twisting of these conduits, the turntable is moved to its alternative positions by an angular back and forth movement rather than successive angular movements in the same direction. The means for rotating the turntable may be of various types but in the form shown comprises a reversible electric motor 39 connected through a drive belt 40 to a gear mechanism in housing 41 which is adapted to` swing an arm 42 whichhas a pivoted connection 43 at its outerlend to the corresponding outer end of an arm 44 secured on depending shaft 45 which in turn is secured coaxially of the turntable in the circular bracket 35 ixed `t-o the1turntableframe parts.

The means forreciprocating the carriage 30 on tracks 32 is shown particularly in Figure 3. Secured :to the under side of the tracks 32 are stationary racks 50 with which mesh a pair of driven gears 51 and also a pair of idler gears 52 one of which is shown in Figure l, a corresponding gear 52 being located `on the opposite side. Each of the driven gears 51 is mounted on a shaft 53 and the drive for the-,shafts `53 yis from a common electric motor `54 which. `througha'suitable gear box lmechanism 55 drives the opposed shafts 56 which are connected through suitable coupling means 57 to the corresponding shafts 53. The electric motor 54 is reversible, and upon suitable positioning of areversing switch 183 (Fig. 6) and closing of the main switch the motor 54 will traverse the carriage to the left to position the flask 12 in the furnace as shown in dotted line at 12 (Fig. l). After the processing of the materials in the flask has occurred, the reversing switch 183- for them'otor having been moved to the opposite position and-the motor thereafter energized, it operates to withdraw the carriage to the mid position shown in -Figure 1. After the turntable has .been rotated 180 the motor will similarly `advance the flask 12a into the furnace 'and withdraw it.

As heretofore noted, the flasks 12 and 12a are removablymounted on the carriage. The supporting means for eachflaskcomprises a rotary spindle which serves not only vtosupport the flask but also to rotate it at appropriate times'undera suitable control. The details of one of the spindles and the means for lsecuring thereon its iiask are shownparticularlyinFigure 5. A pair of spaced roller Vbearings 61'mounted on the carriage, support a hollow spindle -62 provided with a driving means through the sprocket 63 at the right end and adapted to have secured thereto atthe left end a flask such as the flask 12. The spindle isV held against endwise movement by suitable collars 64. v

Th'e spindle is threaded on the left end thereof a bushin'g`65 secured in place by a locking screw 66. A collar 67 is 'adjustable on external threads of the bushing 65. The bushing 65 carries a plurality of latches 68 of which there may be three equally spaced around the bushing, each latch being mounted on a pivot 69 between a pair of lugs 70. The latches are each normally urged to anpopen position by a spring 71, but are adapted to be forced in the opposite direction by outward adjustment of the collar 67. Each flask has secured thereto a metal sleeve 72 provided with an annular groove 73 in which the outer cam lingers 68a of the latches 68 are adapted to engage. Outward adjustment of the collar 67 on the bushing 65 forces the cam ends 68a of the latches into the annular groove 73 and clamps the end of the flask Y against the outerend of the spindle, the bushing 65 being provided with fan enlarged bore adapted to receive the end of the flask ysleeve 72. Preferably a sealing gasket 74 is inserted between 'the complemental ends of the flask and the spindle.

At the opposite end of the spindle is located means, as heretofore noted, for rotating the-spindle through the sprocket 63 and also means for admitting thereto certain desired gases 'while the spindle and flask are being rotated. Themeans referred to includes a collar 76 secured to the end of the spindle'as by means of a threaded connection 77. The sprocket 63 is secured to the collar 76 through the medium of three or more equally spaced bolts 78 extending through holes in the-sprocket and collar 76. The same bolts 78 also extend through an outer ring 79 adapted to rotate with the sprocket'63. A closure cap 80 is located over the end of the hollow spindle, the cap having an inner diametrically reduced portion 80a adapted to lit into the end of an inner sleeve 62a with which the spindle is'provided. The cap 88 is held nonrotatable by means of a U-shaped linger 81 having one end extending into a hole in the cap and the other end secured in a lug 82 fastened to aportion of the base of the carriage. For effecting a` tight seal a gasket 83 is mounted in an annular groove in the cap 80 and is adapted to engage against the end of the spindle-62.

Suitable conduit means are connected through the cap 80 and spindle into the interior of the flask. These include a main central inlet duct 84 extending through an inner supporting bushing 85 and on into the interiorV of thecap '80 whereby a continuous flow of gases into and from the interior of the flask may be maintained, the

exhaust gases escaping by Way of openings through the bushing 85, the hollow spindle, and out the duct 86. The maintenance of the proper gas mixture free of air or impurities within the flask is very important during the deposition portion of the cycle and to this end a continuous flow of inert sealing gasto the outer end of the spindle is provided through means of the duct 87 adapted to direct an inert gas into the space S8 whereby the seal is continuously bathed by a flow of inert gas under sufficient pressure to prevent any air, for example, from leaking into the flask.

Each spindle and its flask are adapted to be independently rotated by power meansmounted on-and movable with the carriage 30. Such means comprises an electric motor 89 driving a sprocket 90 through gear reduction means in the gear box 91. The sprocket 90 is connected to drive the respective sprocket 63 through a chain 92.

The gears used in the operation of -the apparatus are supplied to the inlet duct84 from suitable sources (not shown). The flow of these gases may be controlled either manually or automatically by suitable valves in the supply lines. Likewise the sealing gas is supplied to duct 87 from a suitable source.

Fig. 6 which shows the electrical conrtol circuit, will be described in detail with regard to the description of the operation of the apparatus. This circuit is connected to the main power line L through the main switch 150, and the line L is preferably protected by a fuse 151. Indicator lamp 152 is placed on the control panel to show the operator when the' main power switch 150 is in closed position.

The operation ofthe apparatus is as follows. Assuming `a`ask 12 has been charged with ceramic blanks and mounted on the apparatus and is inthe position shown in Fig. l and Fig. 2. In this position of the turntable and carriage, the micro-switch 138 is closed by cam 135 (see also Fig. 1). Through switch 138 closed, relay 154 is energized and contact 157 is closed to condition the latch coil 173 of relay 172 to be energized subsequently when contact 179 of relay 180 is closed.

Since the carriage is at rest in the center of the turntable microswitch 127 is also closed by cam 128 (see also Fig. l and Fig. 2). Relay 161 is thus connected across the power lineV through closed switch 127 and contact 163 is closed. Micro-switch 129 (see also Fig. 2) is also closed by the presence of the carriage at rest in the center of the turntable, and relay 166 is connected across the power line L to close its contacts 167 and 168. Closure of contacts 167 and168 conditions the door opening relay to be energized. n

Manually-operated switch 1,70 is now closed by the operator, thereby operating the flask rotation motor 89. The door-operating relay 175 is now energized by the operator momentarily closing push button switch 176 which completes a circuit to relay 175 through thepreviously closed contact 168 of relay 166 and the'normally closed contact 178 of unenergizedrelay 180.

The door opening solenoid 22a lis energized through closed contact 181 of relay. 175, while the door closing solenoid 22h is simultaneously de-energized by the opening of contacts' 182 of relay'175. Door opening solenoid -22a' operates valve 22 (see also Fig. 1) which admits air to the door opening -cylinders 16 (see Fig. 4). The furnace doors now open and in their outermost vposition engage and close micro-switches '125 and 126'(see also Fig. 2 and Fig. 4). The closing of switches 125 and 126 yenergizes relay 185 which, by opening its contact 186, `disconnects the circuit to the turntable drive motor39 to assurethat no rotation of the turntable can occur while the flask is in the furnace. Contact 187 of relay185'closes to complete a circuitthrough-close'd contact V181fofrelay 175 to energize the carriage drive motor `54 to move the flask into the furnace.

`Micro-switch `127 [is now opened as it leaves cam 128 (see Fig. 1 and Fig. 2)jbythe carriagemovement from its idle center position and relay 161 is thereby de-energized. Release of relay 161 opens contact 163 which introduces an additional discontinuity in the turntable rotation motor circuit. t i l When a'sk 12 reaches its extreme forward position and is all the way inside the furnace, micro-switch 129 is opened by engagement withlcam 130 (Fig.V 1` and Fig. y2) to de-energize relay 166. Contacts 168 of relay 166 now open and de-energize relay 175. Thenormally closed contact 182 of relay 175 now completes a circuit to operate the` door closing solenoidV 22b` which shifts valve 22 (Fig. 1) to cause the furnace doors to closear'ound the neck of the flask 12 `as shown bylthe dotted indication of the flask 12 in Fig. Y1 .of thedrawing. Simultaneously with thisoperation, contact 181 of relay 175 opens to de-energize the door opening solenoid 22a.

By the opening of contact 167 on de-energized relay 166, which has just been open-circuited by operation of micro-switch 129 when the ask reached its innermost position in the furna-ce, relay 185 is open-circuited to disconnect the carriage travel motor 54 through the opening of contact 187. t

The gases are then admitted into the ask through inlet duct 84. After the desired time for treatment the gases are turned off and the operator closes switch 183. The

closing of switch 183 energizes relay 180 which through its contactors 178 and 179 reverse connection of the circuit to the carriage motor 54, conditioning this motor to withdraw flask 12 from the furnace. Contactor 177 of relay 189 conditions relay 185 to be energized when micro-switches 125 and` 126 are closed. Contactor 178 on relay 180 operated also completes a circuit for the energization of relay 175. Contacts 181 of relay 175 operated close a circuit to energize the door opening solenoid 22a, while contacts 182 open a circuit simultaneously to de-energize the door closing solenoid 22b. This, as previously described, opens the furnace doors which, when fully open, close micro-switches 125 and 126 to energize relay 185. Contacts 187 of relay 185 close to complete the power circuit for carriage motor 54 whereupon the carriage motor withdraws ask 12 from the furnace.

When the carriage reaches its center position and flask 12 has been completely withdrawn from the furnace, micro-switch 127 is closed by cam 128 (see Fig. 2) to energize relay 161. Contacts 163 of relay 161 close to condition the turntable rotating motor 39 to rotate the turntable through 18() degrees when the operator presses turntable reverse switch 155. Meanwhile the operator opens switch 183 which de-energizes relay 180. This causes the relay 175 to be de-energized and the contacts 182 of relay 175 energize the door closing solenoid 22b and deenergize the door opening solenoid 22a, thereby closing the furnace door. The de-energizing of relay 180 causes the contacts 179 to reverse the carriage travel motor 54 preparatory to moving the next ask into the furnace. Meanwhile it may be assumed that the operator has ycharged the second flask 12a, as seen in Fig. l and Fig. 2

and that the contents of this second flask are now ready for processing. Accordingly, when the operator presses the turntable reverse switch 155, the second flask 12a is moved into the position previously occupied by ask 12 adjacent to the furnace doors, and another cycle of operation can be repeated as herein described.

The mechanism also includes a blower which delivers a blast of air to the withdrawn flask for cooling it. The mechanical parts for this purpose are shown particularly in Figure l and include a blower 140 adapted to deliver air through the pipe 141 to a suitable outlet 142 adjacent the corresponding flask when the carriage is moved to the left to position the other flask in the furnace. In other words, when a flask upon the completion of the cycle is withdrawn and the turntable indexed, the other ask will have been recharged and the apparatus is ready for the moving of the rechargedtask into the furnace which brings the hot,` juist-withdrawn'flask` over vthe outlet-|142` I of the blower. The blower is adapted to be driven any suitable means such as the electric motor 143. In general, since the normal time of treating a ask in the furnace requires several hours, the blower may continue to operate for some period of time after a ask is withdrawn from the ,furnace and positioned over the outlet whereby it may be adequately cooled before the operator need remove it, and there will remain ample time for the flask to berecharged and replaced before the completion of the treatment of the flask in the furnace. n

, It will be understood also that the flasks are contin-` uously rotated at a relatively slow rate while in thefurnace and preferably. whileY being exposed to the cooling blast after being withdrawn. When theflask is cooled the rotation is stopped by opening switch so that the flask can be emptied and recharged in preparation for the next cycle.

Since certain changes may be made in the above construction and different embodiments of the invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

I claim:

1.` In an apparatus for successively positioning carbon deposition flasks in a furnacechamber the combination of, a supporting base, a turntable rotatably mounted thereon, a carriage translatably mounted on said turntable, means for independently supporting on said carriage a pair of carbon deposition `iasks extending laterally outward in a horizontally angularly spaced relation, the supporting means embodying a rotatable element and means for releasably clamping the neck portion of the flask there to, means for rotating each of said elements and its ask independently of the other, a furnace chamber positioned adjacent said carriage and adapted to receive successively therein said flasks, means for rotating said turntable to predetermined angular positions appropriate to presenting the respective flasks to said chamber, and means for translating said carriage to move the corresponding flask into and out of said chamber.

2. -In a machine for withdrawably position-ing elements in a treating chamber the combination of, a base having a horizontal circular track, va turntable rotatably supported on said track, means for rotating said turntable forward and back to predetermined positions angularly spaced by a pair of spacedphorizontaltracks on said turntable, a carriage translatably mounted on said tracks, means for supporting on said carriage a pair of elements to be treated angularly spaced horizontally 180, said carriage having a norm-al retracted position midway of the length of said horizontal tracks, and means for selectively translating said carriage to an outer position toward either end of its tracks for presenting the corresponding element to said chamber.

3. In an apparatus for successively hold-ing carbon deposition flasks in a furnace chamber the combination of, a base having a horizontal circular track, a turntable rotatably supported on said track, means for rotating said turntable forward and back t=o predetermined positions angularly spaced by 180, a pair of spaced horizontal tracks on said turntable, a carriage translatably mounted on said tracks, means for releasa-bly supporting on said carriage a pair of carbon deposition flasks each projecting outwardly and angularly spaced horizontally 180, means for independently rotating each of said asks, said carriage having a normal retracted position midway of the length of said horizontal tracks, and means for selec` tively translating said carriage to an outer position toward either end of its tracks for presenting the corresponding flask to the furnace chamber.

4. In a machine for withdrawably supporting carbon deposition flasks in a furnace the combination of a snpf porting base, a Iturntable rotatably supported thereon, a

carriage mounted 'for horizontally translatory movement on :said turntable, means for translating sia-id carriage, a pair 'of flasks yindependently supported on said carriage the mounting means for each ask comprising a rotatable spindle and means for clamping the-llask in releasable hermetically'sealed relation endwise to its corresponding spindle, and means for rotating each spindle and its corresponding flask independently of the other.

5. =In a mach-ine for successively holding carbon deposition a-sksin a furnace the combination `of, a supporting base, a turntable rotatably supported thereon, a carriage mounted for horizontally translatory movement on said turntable, means for translating said carriage, a pair of -asks independently supported on said carriage the mounting means for each flask comprising a rotatable ASpindle and means for clamping the end opening of the i 'ask in releasable Ahermetically zsealed relation endwise ReferencesCited in the le of this patent UNITED STATES PATENTS 888,175 Kendall May 19, 1908 1,259,023! Kendall Mar. l2, 1918 2,622,861 Talley Dec. 23, 1952 FOREIGN PATENTS Great Britain Apr. 23, 1929 

